Investigate the larvicidal efficiency of selected botanical plant extracts against dengue vector Aedes sp.

Abstract

The global rise in mosquito-borne diseases, particularly dengue fever, emphasizes the need for eco-friendly vector control methods. This study investigates the larvicidal potential of five medicinal plants such as Nicotiana tabacum (Tobacco), Acorus calamus (Sweet Flag), Pongamia pinnata (Pungam), Calotropis sp., and Aristolochia bracteolate (Worm Killer) against Aedes sp. larvae. All selected plant extracts were prepared by using methanol as a solvent and larvicidal mortality was assessed 24 hrs with different concentration ranges from 25-500 ppm for each extract. The highest mortality was observed in Acorus calamus with 98.00% ± 2.45 reduction at 500 ppm alongside the lowest LC50 of 58.07 ppm ± 0.80, LC90 of 557.82 ± 0.75 and LC99 of 1103.22 ± 0.75. Calotropis sp. demonstrate moderate effectiveness with a 93.00% ± 2.45 mortality rate at 500 ppm and an LC50 of 97.27 ppm ± 0.75. In contrast, Aristolochia bracteolate was the least effective, resulting in a mortality rate of 67.00% ± 5.10 at 500 ppm, an LC50 of 330.47 ppm ± 0.4, an LC90 of 1208.20 ± 0.63, and an LC99 of 2166.09 ± 1.02. One-way ANOVA confirmed significant differences in mortality across extracts (p < 0.001), and Tukey’s post-hoc test revealed Acorus calamus was significantly more effective than Pongamia pinnata and Aristolochia bracteolate (p < 0.05). Regression analysis indicated a strong dose-response relationship for all extracts, with Acorus calamus showing the highest regression coefficient (0.22) and Aristolochia bracteolate the lowest (0.08). Phytochemical screening identified key bioactive compounds such as phenols, terpenoids, and alkaloids. Effect size analysis (Cohen’s d = 1.72) between Acorus calamus and Aristolochia bracteolate highlighted substantial differences in efficacy. These findings demonstrate the strong potential of Acorus calamus as a promising natural larvicide, while Aristolochia bracteolate is less effective, suggesting that a higher concentration or combination of plant extracts might be needed for optimal mosquito control.